Python makes Windows system services

Recently, an Python program needs to be installed and run as Windows system service. During the process, I encountered some pits and cleaned up one.

Python service class

First of all, Python program needs to call some Windows system API to serve as the system. The details are as follows:

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import sys
import time

import win32api
import win32event
import win32service
import win32serviceutil
import servicemanager


class MyService(win32serviceutil.ServiceFramework):

  _svc_name_ = "MyService"
  _svc_display_name_ = "My Service"
  _svc_description_ = "My Service"

  def __init__(self, args):
    self.log('init')
    win32serviceutil.ServiceFramework.__init__(self, args)
    self.stop_event = win32event.CreateEvent(None, 0, 0, None)

  def SvcDoRun(self):
    self.ReportServiceStatus(win32service.SERVICE_START_PENDING)
    try:
      self.ReportServiceStatus(win32service.SERVICE_RUNNING)
      self.log('start')
      self.start()
      self.log('wait')
      win32event.WaitForSingleObject(self.stop_event, win32event.INFINITE)
      self.log('done')
    except BaseException as e:
      self.log('Exception : %s' % e)
      self.SvcStop()

  def SvcStop(self):
    self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
    self.log('stopping')
    self.stop()
    self.log('stopped')
    win32event.SetEvent(self.stop_event)
    self.ReportServiceStatus(win32service.SERVICE_STOPPED)

  def start(self):
    time.sleep(10000)

  def stop(self):
    pass

  def log(self, msg):
    servicemanager.LogInfoMsg(str(msg))

  def sleep(self, minute):
    win32api.Sleep((minute*1000), True)

if __name__ == "__main__":
  if len(sys.argv) == 1:
    servicemanager.Initialize()
    servicemanager.PrepareToHostSingle(MyService)
    servicemanager.StartServiceCtrlDispatcher()
  else:
    win32serviceutil.HandleCommandLine(MyService)

pyinstaller packaging

pyinstaller -F MyService.py

test

#  Installation services 
dist\MyService.exe install

#  Start the service 
sc start MyService

#  Stop the service 
sc stop MyService

#  Remove the service 
sc delete MyService